As of early 2017, the BBC requires all users to sign up and login with a BBC iPlayer ID before they are allowed to watch BBC content.
While the BBC had already changed the requirements to watch catch up TV on September 1st 2016, this had little effect on the actual use of iPlayer as all you had to do was acknowledge that you currently have a TV license and you'll be given access to all of iPlayer's online content.
The change in 2017 still does not enforce the need for a TV license, however in an effort to understand the interests of their viewers better, the BBC requires that you have a login ID so they can better track programmes you've watched, are interested in and potentially create content based on popular programming.
During the registration process, you are free to use any UK based postcode, for example E17 3AA
More information on the 2017 change can be found in the link below:
If you have any questions about this change or need any further assistance, please don't hesitate to contact our support team at firstname.lastname@example.org and we'll do our best to advise further.